US 6,204,710 B1 · Precision trim circuit for delay lines

Abstract

A precision trim circuit for a tuneable delay line is provided. The precision trim circuit provides delays greater than the base delay of the tuneable delay line. By using larger delays than conventional trim circuits, the precision trim circuit of the present invention can use components that react to process and environmental variations in the same manner as the components of the tuneable delay line. Specifically, one embodiment of the precision trim circuit comprises a first delay element providing a delay greater than or equal to the base delay of the tuneable delay line. The precision trim circuit also comprises a second delay element providing a greater delay than the first delay element. A multiplexer coupled to the first delay element and the second delay element is used to select the amount of delay provided by the precision trim circuit. Other embodiments include additional delay elements providing varying delay values.

Claims13

Dependent claims

A delay circuit comprising:

a delay line having a base delay;
and
a trim circuit coupled to the delay line and having
a first delay element having a first delay at least equal to the base delay of the delay line;
a second delay element having a second delay greater than the first delay;
a multiplexer coupled to the first delay element and the second delay element;
a third delay element coupled to the multiplexer, the third delay element having a third delay greater than the second delay;
and
a fourth delay element coupled to the multiplexer, the fourth delay element having a fourth delay greater than the third delay.

6 more elements

Dependencies are inferred from the claim text.

Precision trim circuit for delay lines

Life of this patent

Precision trim circuit for delay lines

Life of this patent

Abstract

Claims13